Iphone 4S getting hot

[ANTREVELL]

I know this is not about sailing but just wondered if anyone has experienced the problem. My phone would suddenly start to get very warm which was a bit disconserting and the battery capacity dropped considerably even though I did not use.
I have now changed the battery to a double capacity but it still gets hot . I have today turned the WIfi off and at the moment it seems to have improved. Not sure when but recently it updated to 9.3 . I was not aware of the problem before this update. Is it possible to go back to the previous version.

Regards Tony cruiser 33  Pegatha

[Lyra]

Never had an Iphone but this is something that happens on all smartphones - an application which you are not aware of being ON is consuming battery. These are typically "location aware" applications that use either or both wifi and gps.
Try to find a good "application manager" application and check which applications are ON. Kill the applications that you do not use.
Also, we sometimes tend to install applications that after the first few days/weeks we never or very seldom use - uninstall them.